Hartree-Fock and 2nd-Order Moller-Plesset Perturbation-Theory Calculations of the P-31 Nuclear-Magnetic-Resonance Shielding Tensor in Ph3
by Wolinski, K.; Hsu, C. L.; Hinton, J. F.; Pulay, P.
The P-31 shielding tensor for PH3 has been calculated without electron correlation (self-consistent field) and with electron correlation (second-order Mollet-Plesset) using the gauge including atomic orbital method. The best results obtained for the absolute isotropic chemical shielding constant (608.09 ppm) and chemical shielding anisotropy (64.54 ppm) compare quite favorably with the experimental values of 600 and 64.5 ppm. The contribution of electron correlation to the absolute shielding value has been found to be significant. The convergence of the calculated shielding tensor with respect to the quality of the basis set employed and the importance of d and f polarization orbitals are discussed.